Portable, personal communication systems, such as cellular telephones and cordless telephones, are currently experiencing a dramatic growth in utilization. Cellular telephones, for example, have enabled users to transcend the constraints of fixed telephony by allowing communication outside of buildings. In accordance with such trends, society will probably witness a significant wireless evolution in both personal and professional communications which will change the way people conduct their lives at home, on the road, and at work.
Personal communication systems generally include a transmitter-receiver pair along with an audio output device and an audio input device. The audio output device typically comprises speakers, headphones, earphones, or the like. In general terms, audio output devices for use with a personal communication system are devices capable of producing sound waves representative of an electronic audio signal applied thereto, and are employed in contact with the ear of the user. The audio input device typically comprises a microphone or a like tranducer. The audio input device is capable of producing an electronic signal representative of sound waves received thereby.
Typically, the audio input and output devices are incorporated on a handset. This arrangement is disadvantageous in that a hand of the user becomes occupied during the communication process. Thus, the user of a handset is limited in the types of activities he/she can perform while simultaneously communicating.
In order to obtain a hands-free system with regard to the audio output device, either headphones or earphones may be employed. Disadvantages of using either headphones or earphones for personal listening result from the ears of the user being partially covered. Consequently, headphones and earphones act to block sound waves produced within the physical environment of the user. Hence, potential safety risks result if the user is performing other tasks while wearing a headphone or an earphone, such as driving a car, crossing a street, or operating a machine. Further, wearing a headphone or an earphone for an extended duration of time grows uncomfortable for many people.
Other disadvantages become evident when interaction is attempted between one person and another person wearing headphones. Often, the one person's speaking and social interaction changes when conversing to the other person wearing headphones, or even a hearing aid. Moreover, these social changes are witnessed even when the one person knows that the other person needs the hearing aid.
In order to obtain a hands-free system with regard to the audio input device, a microphone can be located on a headset, such as is worn by telephone operators and receptionists. Such an arrangement is also socially disadvantageous when attempting to interact with others in her physical space. Furthermore, such an arrangement interferes with a variety of daily activities such as eating or drinking. The use of a headset in a public place is also conspicuous.
Some interface devices have avoided the use of a headset by incorporating an audio output device into a garment worn on the upper torso. However, these prior art devices lack an audio input device to receive input from the user since they were intended as personal music listening systems rather than personal communication systems.
An additional disadvantage of many prior art systems is the inability of these systems to provide and capture high-fidelity sound. These prior art systems distort audio signals to the extent that there is never a question that the sound produced is not natural.